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Mum witnessed son, Tashawn Watt, stabbed to death in Sydenham home by close friend
Denise Campbell broke down in tears several times as the teenager who stabbed her son to death was sentenced to life.
It brought back the painful memories of the day he was murdered. It happened in front of her and in her family home in Sydenham in south east London.
It was 9.30pm on the 25th of June last year, just over two weeks after Tashawn's 19th birthday, when he was fatally stabbed in the chest.
His mother has also had to deal with the knowing Tashawn's killer was not a stranger, but a teenager the family knew well, and Tashawn considered a close friend.
"I was there when it actually happened, when the killing happened and I was there when he died," Denise told ITV News London.
"To see my son in front of me taking his last breath and I couldn't do anything about it, I can't come to terms with it.
"For this to happen from somebody that you were so close with, he stayed here sometimes, it's hard to understand.
"It wasn't a stranger, it wasn't an enemy, it was a friend," she added.
Inner London Crown Court was told the police were called by the family and found Tashawn, who was known as Tata, collapsed just outside the back of the house in SE26.
Emergency workers from London Ambulance Service carried out CPR, but despite their best-efforts Tashawn died at the scene.
Detectives from the Met's Specialist Crime Command began a murder investigation and started urgent enquiries to work out why Tashawn, an aspiring banker, had been attacked.
They established that Romello Harley, who was also 19, had been involved in an argument with a relative of Tashawn's at the Watts' family home a short time before the incident, which resulted in Harley being asked to leave.
He then armed himself with a knife before returning to the area. He tried to lure Tashawn to an alleyway which runs at the bottom of their garden, but Tashawn refused to go with him. Harley then stabbed Tashawn in front of his family.
After the attack, Harley dropped the knife and ran away from the scene. As well as there being several witnesses to the incident, the attack was also caught on CCTV.
The suspect went into hiding and officers began an urgent manhunt to locate him. On 28 June, he handed himself in at Lewisham Police Station and was arrested on suspicion of murder.
Tashawn's family have decided to stay in the house where he was killed because they hope the good memories, they have of him growing up there, will eventually overshadow the bad ones.
Denise says she is relieved the trail is now over but despite two weeks of evidence, she still does not have the answer to the most pressing question of why Harley turned from a friend into a killer.
Tashawn is the latest teenager to lose his life to knife crime in the area and Denise appealed to those who use knives to settle petty arguments to think about the damage they do. She called their actions, "senseless".